Epoch

means that which bounds in or holds in hand. The
starting-point of a sequence of events harnessed together like a team
of horses; also the whole period of time from one epoch to another. Our
present epoch is the Birth of Christ; previous to this epoch it was the
Creation of the World. In this latter sense the word is synonymous with
era. (Greek, epi-echo.)

“The incarnation of Christ is the greatest moral epoch in the
universe of God.” —Stevens: Parables Unfolded (“The Lost
Sheep,” p. 104).